• 제목/요약/키워드: degree of contribution

검색결과 388건 처리시간 0.029초

소집단 협동 전사활동이 대학생의 영어듣기 능력 향상에 미치는 영향 (Effects of small group transcription activities on university students' English listening comprehension)

  • 한상호
    • 영어어문교육
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    • 제12권1호
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    • pp.257-286
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    • 2006
  • This paper investigates the effects of small group collaborative transcription activities on the improvement of university students' English listening ability. Based on the results of pre-tests, a class of 42 students was subdivided into 11 small homogeneous groups of three to four students. Each group was provided with 7 different news items to be transcribed. Means were compared between pre-test and post-test scores, followed by comparison of transcription errors in content and function words. Finally, students' perception and attitudes about the use of small group transcription for improving listening skills were qualitatively analysed and compared with pre- and post test results. It was found that post test scores highly correlated with improvement of listening ability. It was also found that groups of high degree of collaboration showed improvement in listening ability while lack of collaboration contributed to loss of interests in listening. Students who see process more important were found to make more contribution to the group success than those who place more emphasis on the results.

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Prediction of temperature distribution in hardening silica fume-blended concrete

  • Wang, Xiao-Yong
    • Computers and Concrete
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    • 제13권1호
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    • pp.97-115
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    • 2014
  • Silica fume is a by-product of induction arc furnaces and has long been used as a mineral admixture to produce high-strength, high-performance concrete. Due to the pozzolanic reaction between calcium hydroxide and silica fume, compared with that of Portland cement, the hydration of concrete containing silica fume is much more complex. In this paper, by considering the production of calcium hydroxide in cement hydration and its consumption in the pozzolanic reaction, a numerical model is proposed to simulate the hydration of concrete containing silica fume. The heat evolution rate of silica fume concrete is determined from the contribution of cement hydration and the pozzolanic reaction. Furthermore, the temperature distribution and temperature history in hardening blended concrete are evaluated based on the degree of hydration of the cement and the mineral admixtures. The proposed model is verified through experimental data on concrete with different water-to-cement ratios and mineral admixture substitution ratios.

Electron Transport Mechanisms in Ag Schottky Contacts Fabricated on O-polar and Nonpolar m-plane Bulk ZnO

  • Kim, Hogyoung
    • Transactions on Electrical and Electronic Materials
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    • 제16권5호
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    • pp.285-289
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    • 2015
  • We prepared silver Schottky contacts to O-polar and nonpolar m-plane bulk ZnO wafers. Then, by considering various transport models, we performed a comparative analysis of the current transport properties of Ag/bulk ZnO Schottky diodes, which were measured at 300, 200, and 100 K. The fitting of the forward bias current-voltage (I-V) characteristics revealed that the tunneling current is dominant as the transport component in both the samples. Compared to thermionic emission (TE), a stronger contribution of tunneling current was observed at low temperature. The reverse bias I-V characteristics were well fitted with the thermionic field emission (TFE) in both the samples. The presence of acceptor-like adsorbates, such as O2 and H2O, modulated the surface conductive state of ZnO, thereby affecting the tunneling effect. The degree of activation/passivation of acceptor-like adsorbates might be different in both the samples owing to their different surface morphologies and surface defects (e.g., oxygen vacancies).

확장형 에지 선소를 이용한 스테레오 정합 (Stereo Matching using the Extended Edge Segments)

  • 손홍락;김형석
    • 대한전기학회논문지:시스템및제어부문D
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    • 제51권8호
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    • pp.335-343
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    • 2002
  • A segment matching algorithm in stereo vision via the fusion of multiple features on long edge segments is proposed. One problem of the previous segment matching algorithm is the similarity among the segments caused from its short length. In the proposed algorithm, edges are composed of longer segments which are obtained by breaking the edges only at the locations with distinguished changes of the shape. Such long segments can contain extra features such as curvature ratio and length of segments which could not be included in shorter ones. Use of such additional features enhances the matching accuracy significantly To fuse multiple features for matching, weighting value determination algorithm which is computed according to the degree of the contribution of each factor is proposed. The stereo matching simulations with the proposed algorithm are done about various images and their results are included.

Effects of attention on the perception of L2 phonetic contrast

  • Lee, Hyunjung
    • 말소리와 음성과학
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    • 제6권4호
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    • pp.47-52
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    • 2014
  • This study investigated how the degree of attention modulates English learners' perception of Korean stop contrasts. The contributions of VOT and F0 in perceiving Korean stops were examined while availability of attentional resources was manipulated using a dual-task paradigm. Results demonstrated the attentional modulation in the use of VOT, but not in F0: under less attention, the contribution of VOT to the perception of aspirated stops decreased, whereas that of lenis stops increased, which suggests more native-like performance. This implies that the role of attention in perceiving non-native contrasts might differ depending on how equivalent the acoustic and perceptual cues are between L1 and target L2 contrasts.

A MIXED NORM RESTORATION FOR MULTICHANNEL IMAGES

  • Hong, Min-Cheol;Cha, Hyung-Tae;Hahn, Hyun-Soo
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 제13회 신호처리 합동 학술대회 논문집
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    • pp.399-402
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    • 2000
  • In this paper, we present a regularized mixed norm multichannel image restoration algorithm. The problem of multichannel restoration using both within- and between- channel deterministic information is considered. For each channel a functional which combines the least mean squares (LMS), the least mean fourth(LMF), and a smoothing functional is proposed, We introduce a mixed norm parameter that controls the relative contribution between the LMS and the LMF, and a regularization parameter that defines the degree of smoothness of the solution, both updated at each iteration according to the noise characteristics of each channel. The novelty of the proposed algorithm is that no knowledge of the noise distribution for each channel is required, and the parameters mentioned above are adjusted based on the partially restored image.

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제주지역 풍력발전기에 의한 전력계통운영 영향분석 (Power Network's Operation Influence Analysis of Wind Power Plant in Jeju island)

  • 김영환;최병천;장시호;김세호;좌종근
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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    • pp.127-129
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    • 2005
  • Construction of wind power plant is increasing rapidly because Jeju island is known as the most suitable place for wind power plant. Rut wind power plant is difficult electric power control and it has a rapid electric power fluctuation. Such a problem has a bad influence on electric power network in small electric network like Jeju. Therefore, we forecast the amount of wind power plant construction by weather information and the rate of utilization for existing facility. We investigate the contribution degree for electric Power demand, economic effect, the case of power network influence. So we forecast influence of wind power plant for Jeju power network's operation in the near future.

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Development of Expertise-based Safety Performance Evaluation Model

  • Yoo, Wi Sung;Lee, Ung-Kyun
    • 한국건축시공학회지
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    • 제13권2호
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    • pp.159-168
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    • 2013
  • Construction projects have become increasingly complex in recent years, resulting in substantial safety hazards and frequent fall accidents. In an attempt to prevent fall accidents, various safety management systems have been developed. These systems have mainly been evaluated qualitatively and subjectively by practitioners or supervisors, and there are few tools that can be used to quantitatively evaluate the performance of safety management systems. We propose an expertise-based safety performance evaluation model (EXSPEM), which integrates a fuzzy approach-based analytic hierarchy process and a regression approach. The proposed model uses S-shaped curves to represent the degree of contribution by subjective expertise and is verified by a genetic algorithm. To illustrate its practical application, EXSPEM was applied to evaluate the safety performance of a newly developed real-time mobile detector monitoring system. It is expected that this model will be a helpful tool for systematically evaluating the application of a robust safety control and management system in a complex construction environment.

Perturbation method for the dynamic analysis of a bistable oscillator under slow harmonic excitation

  • Luongo, Angelo;Casciati, Sara;Zulli, Daniele
    • Smart Structures and Systems
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    • 제18권1호
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    • pp.183-196
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    • 2016
  • In this paper a nonlinear, bistable, single degree of freedom system is considered. It consists of a Duffing oscillator externally excited by a non-resonant, harmonic force. A customized perturbation scheme is proposed to achieve an approximate expression for periodic solutions. It is based on the evaluation of the quasi-steady (slow) solution, and then on a variable change followed by two perturbation steps which aim to capture the fast, decaying contribution of the response. The reconstructed solution, given by the sum of the slow and fast contributions, is in a good agreement with the one obtained by numerical integration.

日本国内における都市商業の集客モデルに関する考察 (Hypothesis of Customer Attraction Model in Metropolitan Area Unit)

  • 吉田創
    • Journal of East Asia Management
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    • 제2권1호
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    • pp.23-48
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    • 2021
  • The consumer is living in the frame which is called a city and is leading life through "the purchase act". As for there not being "the purchase act", our life doesn't stand up. It is possible to say that the retail trade it therefore occupies the mailbox which is important in the urban function. However, as for former research, the functional model about the retail trade in the city leaned to the gross income of the customer development degree of each retail store and the retail trade in the city and the overall show of the model of "the role of the retail trade in the city" wasn't done. Therefore, at this article, it focuses on the retail business status, the chain store which has a multitude ready in the retail trade, and it has a purpose of seizing out boiling and considering and making a new hypothesis about how the retail trade which is one of the urban functions contributes to the city.